Today, various portable devices have been developed and are widely used. Of these portable devices, a cellular phone, an MP3 player, a PMP (portable multimedia player), a laptop computer, a netbook computer, a smart phone, a tablet PC and the like are popularly used. Generally, when users of these portable devices go outdoors, they carry their portable devices, or when the users come indoors, they place their portable devices on a desk or table.
These portable devices enable users to enjoy multimedia information in a state of conveniently holding the device with their hands or to simply perform his or her work by driving other programs, and can be used even when users are walking or are riding on a bus or subway.
However, with the development of the iPad as a starting point, tablet PCs have been recently developed, and thus, a user can conveniently use his or her portable device while carrying it outdoors, thereby enabling the user to easily search for information or listen to music in a bus or subway.
The frequency in use of these portable devices indoors as well as outdoors has been continuously increasing, and in order to conveniently use them indoors, a separate holder has been used so that a user can enjoy multimedia contents with his or her portable device placed on a horizontal plane such as a desk and the like.
Although a conventional holder is configured so that the user can enjoy various kinds of multimedia contents in a car or in a state of his or her portable device being placed on a desk without holding it in his or her hand, it is difficult for the holder composed in a single stage form to change and fix holding positions of the device as the user wishes, and there is also inconvenience in that the step of fixing the holder to a desired position should be performed.
In order to eliminate the fixing step, a ball hinge has been developed as a solution. The ball hinge is compressed by an elastic force, but there is the inconvenience that the user should apply much force to the holder in order to change the position thereof when the holder is provided with the elastic force of a spring so as to endure the load of a product such as the iPad.
Although the hinge structure connected to the holder and fixed to be compressed by the elastic force can be freely rotated or can be horizontally and vertically moved freely, the hinge structure endures the load of a product such as an iPad in a vertical state, but a fixed state thereof can be easily released in a slanted state because the hinge structure is supported by only the elastic force.